We have 55% and 80% antifreeze. We need 90 gallons of 75%.
F - 55% and E - 80%
A) F + E = 90
B) .55 F + .80 E = 67.50 (which is .75 * 90) Multiplying A) by -.55
A) -.55 F -.55 E = -49.50 (which is -.55 * 90) then adding A) & B)
.25 E = 18
E = 72 gallons of 80% and
F = 18 gallons of 55%
********* DOUBLE CHECK ******************
72 * .80 = 57.60 and 18 * .55 = 9.90
57.60 + 9.90 = 67.50 gallons of antifreeze and we have 90 total gallons
(67.50 / 90) * 100 = 75% correct!
Source: 1728.com/mixture.htm
Answer:
2x^2+4x-30=0
Step-by-step explanation:
2x^2+10x-6x-30=0
2x(x+5)-6(x+5)=0
(2x-6)(x+5)=0
2x-6=0 x+5=0
x=6/2 x=-5
x=3
Answer:
The amount of money Angelica will have at the end of five weeks if d = $25 is $175.
Step-by-step explanation:
The given information are;
The allowance Angelica earns for baby sitting = d dollars per week
The amount she receives as allowance = $10 per week
The amount she will have at the end of 5 weeks = (10 + d)·5
The amount, A, of money Angelica will have at the end of five weeks if d = $25 is given as follows;
A = (10 + 25) × 5 = $175
The amount of money Angelica will have at the end of five weeks if d = $25 is $175.
Answer:
C.
.
Step-by-step explanation:
Let r represent the cost of one packet of radish seeds and let t represent the cost of one packet of tomato seeds.
Roman spent $62.75
This implies that,
Roman bought 32 packets of seeds and one packet of radish seeds costs
$ 1.75.
One packet of tomato seeds costs $ 2.50.
This implies that,
Using guess and check means we substitute into the given equation.
A) We substitute
into both equations.
Both equations are not satisfied.
B)
We substitute
into both equations.
Both equations are not satisfied.
C)
We substitute
into both equations.
Both equations are satisfied.
Hence the solution is,
D) We substitute
into both equations.
Both equations are not satisfied.